Wildlife Management Programmehttp://hdl.handle.net/10523/17152016-12-09T17:16:07Z2016-12-09T17:16:07ZUsing technology to track animal behaviour: Assessing instrumentation effects and the use of accelerometry to identify behaviours in domestic catsCoughlin, Cayley Elisehttp://hdl.handle.net/10523/51022014-11-04T01:03:50Z2014-11-03T03:05:27ZUsing technology to track animal behaviour: Assessing instrumentation effects and the use of accelerometry to identify behaviours in domestic cats
2014
Coughlin, Cayley Elise
Animals involved in studies using tracking devices or data loggers are potentially subject to a range of instrument effects which have a negative impact on survival, reproduction and behaviour. The current recommendation is that device weight shouldn’t exceed 3% of body mass for aerial species and 5% for terrestrial species. However, the 5% rule of thumb has little or no empirical basis and recent studies have found that transmitters weighing less than 3% body mass may still have impacts on energy expenditure and other behavioural parameters. Studies using telemetry and data loggers on domestic cats Felis catus have used collars carrying Kittycams, VHF and GPS tags ranging in weight between 30g - 125g and followed to 5% rule. These studies assume that the device carried is not affecting behaviour, however, this has not been tested quantitatively. The purpose of this research was to examine possible impacts of wearing collared devices of different weights on domestic cat movements and behaviour. Movement data were compared for cats wearing three different GPS collar weights: (1) light, 30g, (2) a medium-heavy, 80g and (3) heavy, a collar weighing approximately 130g. The location error and fix success rate of the GPS was also compared between habitats and different orientations (facing towards the sky, or towards the ground).
Home range size and distance travelled from home were found to be significantly smaller when cats were wearing the heaviest collar treatment. Cats also spent a greater amount of time within the home property when wearing the heaviest collar. There was no difference in habitat use between collar treatments, although habitat categories were broad. The restriction in movement and activity associated with heavy devices may have influenced predation rates by reducing the likelihood of cats encountering prey when home range size were reduced. The light collar treatment (or the medium collar treatment – 2% BM), that weighed <1% of body mass, was suggested as an optimal device weight to reduce the frequency of instrumentation effects.
The other aim of this research was to contribute to the development of an accelerometer that could be used to predict behaviours from movement patterns. Presented here is an initial phase of development, in which behaviours could realistically be distinguished from accelerometry data. Domestic cats wearing an accelerometers were videoed and matched the observed behaviours to the output. It was clear that behaviours observed from movement patterns could be manually (human assisted classification) detected when using calibration videos. Patterns of movement could be discriminated from each other for up to 15 behaviours based on acceleration and angular velocity data. Instantaneous power for both acceleration and velocity were calculated from the tri-axial accelerometer and gyroscopes and these were plotted. With more calibration video footage and a larger sample, it is possible to automatically classify behaviour. In combination with direction (magnetometers), location (GPS devices) and light meters to indicate whether the individual is indoors or in vegetation, accurate information on behaviour and movement can be collected and applied to many areas of behavioural ecology and conservation.
2014-11-03T03:05:27ZDetermining the drivers of yellow-eyed penguin/hōiho (Megadyptes antipodes) productivityYoung, Melanie Janehttp://hdl.handle.net/10523/47112014-03-24T03:10:15Z2014-03-24T03:09:04ZDetermining the drivers of yellow-eyed penguin/hōiho (Megadyptes antipodes) productivity
2014
Young, Melanie Jane
Seabirds are dependent upon marine systems for foraging, dispersion and migration, and on terrestrial systems for breeding, courtship and moulting (McKinlay 2001; Diamond and Devlin 2003). Long-term population studies of seabirds have made it possible to determine the trends in seabird productivity with respect to stochasticity in the marine environment. In this study, 28 years of yellow-eyed penguin/hōiho (Megadyptes antipodes) data were analysed to determine potential drivers of productivity and chick mass in coastal Otago, New Zealand. Hatching rates, chick survival rates and scaled mass (at pre-fledge when chicks are c. 90 days old) were used to determine how breeding hōiho are affected by perturbations in the marine environment in three separate breeding regions on the Otago coast. Using generalised linear mixed models (GLMM), the relationship between sea surface temperature (SST) at two scales, as well as the Southern Oscillation Index (SOI) were determined for each of the hōiho reproductive parameters at lags up to 18 months prior to breeding. In addition the instantaneous effects of weather were included in the models created to account for any additional climatic noise within the breeding season. A subset of data were omitted from the modelling process to determine the predictive capacity of the models, and correlations between these predicted and observed reproductive values were weak (Spearman’s rho: -0.64 to 0.54, p = NS). No single environmental predictor was indicated as a potential ‘driver’ of productivity; system complexity, and the many aspects of climate and weather, the influence of non-climatic processes, as well as the methods chosen, may have obscured a potential environmental predictor of hōiho reproductive success. Fluctuations in the observed reproductive parameters were attributed to the effects of mustelid predation and novel diseases; however the availability of food, both quality and quantity, was thought to be responsible for lower chick survival and mass in some years, and these observations are congruent with prior research (van Heezik 1990ab, 1991). There were clear regional differences in the reproductive parameters, with hōiho in North Otago consistently producing high numbers of quality chicks. Hōiho have adapted to having a reliable foraging area in close proximity to their breeding grounds, and the reproductive strategies they employ, including synchronous hatch of eggs, equal brooding and feeding of chicks, allow for productivity to be maximised, often in spite of adverse environmental conditions, because this closeness may allow for adult hōiho to buffer poor seasons with increased foraging effort without compromising their own survival (Darby and Seddon 1990; Edge 1996; Mattern et al. 2007). The data indicated that extreme inter-decadal La Niña events affect all hōiho breeding parameters, but the models did not always explain variation in these reproductive parameters at other intervals. Monitoring of the Southern Oscillation Index may allow conservation managers to avert chick starvation events in some years, particularly in North Otago and the Otago Peninsula.
2014-03-24T03:09:04ZBreeding biology and conservation management of South Island robins Petroica australis in conifer plantation and native forestsParker, Graham Christopherhttp://hdl.handle.net/10523/42662013-08-29T23:10:18Z2013-08-29T23:07:15ZBreeding biology and conservation management of South Island robins Petroica australis in conifer plantation and native forests
2013
Parker, Graham Christopher
Deforestation is a massive cause of global biodiversity loss. However, although natural and semi-natural forests are declining in global land-area, plantation forests are increasing. Conifer plantation forest cover in New Zealand has increased significantly since the 1950s but the influence of plantation forestry on native avian biodiversity is poorly known. In the Dunedin area, native forests and plantation forests intergrade seamlessly making this region ideal for investigating the life history traits of a native bird species that occupies both forest types, the South Island robin Petroica australis australis. I studied robin nest survival in plantation conifer and native forests in relation to ecologically relevant variables, following breeding of robins at 58 nests over two breeding seasons in conifer plantation forest and one in native forest. In addition relative measures of abundance for key mammalian predators were obtained from 120 tracking tunnels spread over 12 lines and lastly, suggestions for the conservation management of robins are provided.
I found no evidence to support the hypothesis that nest survival is higher in conifer plantation forest than in native forest. For the two years of the study, the opposite pattern was observed; daily nest survival was lower in the conifer site than in the native site. However, there was much better support for nest stage influencing nest survival than site (∆AICc 2.88 vs. 11.07), although the interaction between these two factors had the highest overall support (∆AICc 0). Importantly, this work suggests that native kanuka forests may not be poor robin nesting habitat compared to conifer, as previous survey work has inferred, but further work would be required to confirm this pattern. These results are valuable considering there are no previous estimates of nest survival for the Dunedin robin population, or for robins in conifer plantation forests in New Zealand.
Rats appeared to be more abundant, and mustelids less abundant, in the native forest than in the conifer. Although it is difficult to determine population-level interactions from one year of data, the seasonal changes in rat and mustelid tracking in this study suggest some degree of mustelid control of rats. This might explain why historically, fewer robins were recorded in native forest where there are fewer stoats to control the rats and thus more rats depredating forest birds such as robins; however, nest survival was higher in the native forest than the conifer plantation forest during the two seasons of study.
These results are important for understanding the distribution of South Island robins in the Dunedin area and more importantly, for the future conservation management of this robin population. Ongoing collaborative management and research of the Dunedin robin population, facilitated by the Department of Conservation, is recommended. Suggested management actions include continuing predator control to increase robin nest survival in the Silverstream native forest; drafting an agreement for City Forests to communicate to interested parties when they are going to harvest robin-occupied areas (allowing sufficient time for pre-harvest surveys or other management actions such as translocations ‘out of harm’s way’); harvesting plantation areas containing robins outside of the robin breeding season; and continuing population monitoring to allow management action should the population decrease to an unacceptably low level.
2013-08-29T23:07:15ZThe role of inbreeding in the reproductive fitness of kakapo (Strigops habroptilus)White, Kaitlyn Laurenhttp://hdl.handle.net/10523/41782015-04-28T09:48:50Z2013-07-26T03:42:45ZThe role of inbreeding in the reproductive fitness of kakapo (Strigops habroptilus)
2013
White, Kaitlyn Lauren
As populations decline, inbreeding becomes increasingly unavoidable. Increased genome-wide homozygosity for inbred individuals can result in reduced survival and reproductive fitness (i.e. inbreeding depression), via the expression of deleterious recessive alleles and reduced heterozygosity at over-dominant loci. The tendency for deleterious recessive alleles to drift to high frequencies in small populations means that inbreeding depression can be particularly severe for threatened populations. Therefore, the genetic consequences of small and isolated populations are becoming of increasing concern to conservation biologists.
The kakapo (Strigops habroptilus) is a critically endangered, flightless, nocturnal parrot that now survives only on predator-free island sanctuaries in New Zealand. The recent population bottleneck of 51 individuals, lek mating system and insular origin of all but one of the surviving kakapo, render them particularly susceptible to inbreeding depression. Low productivity of kakapo has been reported and potentially attributed to, an aging population, diet and inbreeding. For this reason, the present study investigated the relationship between inbreeding and reproductive fitness in kakapo.
The preferred method of assessing inbreeding is to use multi-generational pedigree information. However, this is currently unavailable for kakapo, therefore molecular estimates of relatedness were used as a surrogate for pedigree-derived inbreeding coefficients. Internal relatedness and pairwise relatedness were calculated using 25 polymorphic microsatellite loci. The link between relatedness estimates and variation in early life history traits was investigated using heterozygosity-fitness correlations. This was achieved through the use of generalised linear mixed modelling, with an information-theoretic approach and model averaging where necessary. The reproductive traits investigated were female fecundity (clutch size), egg fertility (probability of an egg being fertilised by an individual male), hatching success of fertile eggs (proportion of fertile eggs that a female hatches) and sperm quality (concentration, motility and morphology).
Neither variation in female fecundity nor egg fertility could be attributed to homozygosity with any confidence. Hatching success was determined to be strongly reduced for the more homozygous females and the more homozygous males were determined to have significantly higher proportions of abnormal sperm. Therefore, the present study demonstrated that inbreeding depression is a contributing factor towards reduced reproductive success in kakapo. These findings are consistent with known detrimental effects of inbreeding, in particular for New Zealand endemic species that have experienced severe population bottlenecks. To minimise these effects, and hence reduce potential impacts on population growth and species recovery, kakapo managers should aim to prevent further erosion of genetic diversity and to breed from the descendants of the genetically-distinct Fiordland male Richard Henry. The present study highlights the importance of considering the genetic components of populations in any conservation management program.
2013-07-26T03:42:45ZConservation genetics of island takahe (Porphyrio mantelli)Lettink, Mariekehttp://hdl.handle.net/10523/37502015-04-28T09:43:45Z2013-03-01T03:56:05ZConservation genetics of island takahe (Porphyrio mantelli)
1999
Lettink, Marieke
General introduction:
Conservation of biodiversity is one the most important contemporary global problems faced by humanity. Human activity has caused the extinction of more than a thousand vertebrate species over the last century (Altukhov, 1994), with many more currently on the verge of extinction. As remaining natural areas continue to decline in size and become fragmented, an increasing number of species will require monitoring and management to ensure their persistence.
New Zealand contains 11% of the world's endangered bird species (Reed and Merton, 1990). For many of these species, management options are limited to preserving relic populations and their habitats on the mainland, and/or maintaining a number of small populations on predator-free offshore islands. New Zealand has over 500 offshore islands, a large proportion of which are designated sanctuaries or nature reserves (Mortimer et al., 1996).
Over the last decade, awareness and concern over genetic problems potentially faced by small populations has grown considerably. Issues of particular concern are the maintenance of genetic variation and effects of inbreeding. This project constitutes an investigation into genetic issues related to the management of the takahe (Porphyria mantelli), a large, flightless rail endemic to New Zealand. Presumed extinct until their "rediscovery" in 1948, just one relict population of -120 individuals remains in the Murchison Mountains, Fiordland. In addition, four small populations have been established on predator-free islands since 1984 (Crouchley, 1994).
This project consists of two separate but inter-related chapters. Chapter One addresses the mating system and levels of genetic variation of takahe breeding on islands. Chapter Two assesses the effects of inbreeding on the reproductive success of island takahe. Conclusions and management recommendations are considered in the final part of this report. Some repetition is a consequence of this approach.
ii, 66 leaves : ill. ; 30 cm. A research report submitted in partial fulfilment of the requirements for the Diploma in Wildlife Management. University of Otago department: Zoology. University of Otago Wildlife Management Report; no. 96.
2013-03-01T03:56:05ZEvaluation of bait stations and management options for control of dama wallabies (Macropus eugenii), in the Bay of Plenty, New ZealandWilliams, Dale Shttp://hdl.handle.net/10523/17172015-04-28T09:44:49Z2011-06-06T22:16:25ZEvaluation of bait stations and management options for control of dama wallabies (Macropus eugenii), in the Bay of Plenty, New Zealand
1997
Williams, Dale S
OBJECTIVES:
(1) Review information on the colonisation, impacts and past management of dama wallabies in the Bay of Plenty.
(2) Identify an effective bait station for delivering cereal bait to dama wallabies.
(3) Identify any physical or behavioural characteristics of dama wallabies that may influence the efficacy of using bait stations as a control technique.
METHODS: This report is based on:
(1) A review of the colonisation, impacts, past management practices, and possible options for the control of dama wallabies.
(2) Time-lapse video equipment was used to observe captive wallabies at Rainbow Springs as they feed from three makes of bait station.
(3) Rhodamine dyed non-toxic bait was placed in bait stations at the Okataina Scenic Reserve and Paehinahina Peninsula, Lake Rotoiti. Time-lapse video and faecal pellet searches were used to assess the feeding activity of feral wallabies and possums.
RESULTS AND RECOMMENDATIONS:
• Dama wallabies are continuing to spread within the Bay of Plenty. To prevent further expansion of their feral range, management action must be targeted at sites of highest priority, based on rate of spread, or their proximity to sites of high conservation value, on lands of all tenure.
• Past aerial poisoning operations have achieved very high kills on wallabies, but to allow highly palatable plant species to recover, wallaby numbers will need to be kept at very low levels for a sustained period. The success of control should be judged on vegetation response therefore vegetation monitoring must also continue.
• To make best use of pest control resources, management action on wallabies should be coordinated with the control of other pests and the impacts of control on other wildlife should be monitored
• To ensure control is efficient and sustainable, toxins, baits, and a variety of control options including bait stations need to be tested on wallabies.
• A public awareness campaign on the impacts and dispersal of wallabies should to be initiated, and public concerns about methods of control need to be addressed.
• Captive wallabies were initially reluctant to feed from the "Philproof bait feeder". Of the three stations tested, the Marley downpipe "hockey stick" station was the most preferred by wallabies.
• Bait stations should be mounted with the entrance no higher than 400 mm above the ground, as this provides easy access to bait for all age classes of wallaby.
• During observed interactions between wallabies and possums, wallabies were displaced from the bait station. At Paehinahina possum densities are low (8.5 possums/100 trap nights), there was very little overlap in feeding times and only 4 interactions between wallabies and possums were observed. At Okataina where possum densities are high (c.50 possums /100 trap nights), there was no evidence that wallabies were feeding from the bait stations, though I was unable to confirm that possums were preventing wallabies from accessing bait.
• A well designed management experiments using toxic bait in bait stations, would be the most practical way to further investigate the efficacy and efficiency of bait stations for the control of wallabies. Suitable techniques for monitoring both wallabies and possums are needed. Bait containing a marker dye and time-lapse video are useful techniques for monitoring bait station use.
[8], 96, [33] leaves ; 31 cm. Bibliography: leaves [10-12] (3rd group) "January 1997." University of Otago department: Zoology.
2011-06-06T22:16:25Z